In recent years, from the viewpoint of energy conservation, renewed activity has been seen in attempts to utilize microorganisms or their enzymes as a biocatalyst for matter production. Nitrile hydratase is known as an enzyme which hydrates nitrites to thereby produce the corresponding amides. In particular, it is useful as a catalyst to produce acrylamide from acrylonitrile.
As microorganisms having nitrile hydratase production ability, for example, there are known bacteria belonging to genus Nocardia [see Japanese Patent Application Laying-Open (kokai) No. 54-129190], genus Rhodococcus [see Japanese Patent Application Laying-Open (kokai) No. 2-470], genus Rhizobium [see Japanese Patent Application Laying-Open (kokai) No. 5-236977], genus Klebsiera [Japanese Patent Application Laying-Open (kokai) No. 5-30982], genus Aeromonas [Japanese Patent Application Laying-Open (kokai) No. 5-30983], genus Agrobacterium [Japanese Patent Application Laying-Open (kokai) No. 8-154691], genus Bacillus [Japanese Patent Application Laying-Open (kokai) No. 8-187092], genus Pseudonocardia [Japanese Patent Application Laying-Open (kokai) No. 8-56684], and the like. In each of the above-mentioned publications, a method of cultivating microorganisms which produce nitrile hydratase activity is described.
Further, with respect to use of carbon source in cultivating, it is described in the section “Effect of carbon sources” of Applied Microbiology and Biotechnology (1991) 34:783-788 that “in producing nitrile hydratase by use of R. rhodochroits J1, the most suitable carbon source is 2% glucose.”